Chart

Generate chart images (PNG/JPEG) using Chart.js. Supports bar, line, pie, doughnut, scatter, radar, polarArea, and bubble charts with auto-coloring and customizable titles, legends, and dimensions.

Package: @robinpath/chart | Category: Analytics | Type: Integration

Authentication

No authentication required. All functions are available immediately.

Use Cases

Use the chart module when you need to:

• Create a new chart (bar, line, pie, doughnut, scatter, radar, polarArea, bubble) -- Use chart.create to perform this operation
• Add a dataset to an existing chart -- Use chart.addDataset to perform this operation
• Update chart options (title, size, legend, type, labels) -- Use chart.update to perform this operation
• Render chart and save to PNG or JPEG file -- Use chart.save to perform this operation
• Render chart and return as base64 data URL string -- Use chart.toBase64 to perform this operation

Quick Reference

Function	Description	Returns
create	Create a new chart (bar, line, pie, doughnut, scatter, radar, polarArea, bubble)	Chart creation info
addDataset	Add a dataset to an existing chart	Updated dataset count
update	Update chart options (title, size, legend, type, labels)	Update confirmation
save	Render chart and save to PNG or JPEG file	Save result with file size
toBase64	Render chart and return as base64 data URL string	Base64 data URL (data:image/png;base64,...)
toBuffer	Render chart and return as raw Buffer	PNG buffer
destroy	Remove chart from memory	Destroy confirmation

Functions

create

Create a new chart (bar, line, pie, doughnut, scatter, radar, polarArea, bubble)

Module: chart | Returns: object -- Chart creation info

chart.create "c1" "bar" {"labels": ["Q1","Q2"], "datasets": [{"label": "Sales", "data": [100,200]}]} {"title": "Revenue"}

Parameter	Type	Required	Description
id	string	Yes	Unique chart identifier
type	string	Yes	Chart type: bar, line, pie, doughnut, scatter, radar, polarArea, bubble
data	object	Yes	{labels: string[], datasets: [{label, data, backgroundColor?, borderColor?}]}
opts	object	No	{width?, height?, title?, backgroundColor?, indexAxis?, legendPosition?, showLegend?}

---

addDataset

Add a dataset to an existing chart

Module: chart | Returns: object -- Updated dataset count

chart.addDataset "c1" {"label": "Costs", "data": [50, 80]}

Parameter	Type	Required	Description
id	string	Yes	Chart ID
dataset	object	Yes	{label, data, backgroundColor?, borderColor?, borderWidth?}

---

update

Update chart options (title, size, legend, type, labels)

Module: chart | Returns: object -- Update confirmation

chart.update "c1" {"title": "Updated Title", "width": 1200}

Parameter	Type	Required	Description
id	string	Yes	Chart ID
opts	object	Yes	{title?, width?, height?, backgroundColor?, type?, legendPosition?, showLegend?, labels?}

---

save

Render chart and save to PNG or JPEG file

Module: chart | Returns: object -- Save result with file size

chart.save "c1" "./output/chart.png"

Parameter	Type	Required	Description
id	string	Yes	Chart ID
filePath	string	Yes	Output file path
opts	object	No	{format?: 'png'

---

toBase64

Render chart and return as base64 data URL string

Module: chart | Returns: string -- Base64 data URL (data:image/png;base64,...)

chart.toBase64 "c1"

Parameter	Type	Required	Description
id	string	Yes	Chart ID
opts	object	No	{format?: 'png'

---

toBuffer

Render chart and return as raw Buffer

Module: chart | Returns: object -- PNG buffer

chart.toBuffer "c1"

Parameter	Type	Required	Description
id	string	Yes	Chart ID

---

destroy

Remove chart from memory

Module: chart | Returns: object -- Destroy confirmation

chart.destroy "c1"

Parameter	Type	Required	Description
id	string	Yes	Chart ID

---

Error Handling

All functions throw on failure. Common errors:

Error	Cause
Chart "..." not found	Check the error message for details
Chart "..." already exists	Check the error message for details

@desc "Create and validate result"
do
  set $result as chart.create "c1" "bar" {"labels": ["Q1","Q2"], "datasets": [{"label": "Sales", "data": [100,200]}]} {"title": "Revenue"}
  if $result != null
    print "Success"
  else
    print "No result"
  end
enddo

Recipes

1. Create a new item with create

Create a new resource and capture the result.

set $result as chart.create "c1" "bar" {"labels": ["Q1","Q2"], "datasets": [{"label": "Sales", "data": [100,200]}]} {"title": "Revenue"}
print "Created: " + $result

2. Create and update workflow

Create an item and then update it.

@desc "Create and update"
do
  set $created as chart.create "c1" "bar" {"labels": ["Q1","Q2"], "datasets": [{"label": "Sales", "data": [100,200]}]} {"title": "Revenue"}
  # Update the created item
  chart.update "c1" {"title": "Updated Title", "width": 1200}
enddo

3. Multi-step Chart workflow

Chain multiple chart operations together.

@desc "Create, add dataset, and more"
do
  set $r_create as chart.create "c1" "bar" {"labels": ["Q1","Q2"], "datasets": [{"label": "Sales", "data": [100,200]}]} {"title": "Revenue"}
  set $r_addDataset as chart.addDataset "c1" {"label": "Costs", "data": [50, 80]}
  set $r_update as chart.update "c1" {"title": "Updated Title", "width": 1200}
  print "All operations complete"
enddo

4. Safe create with validation

Check results before proceeding.

@desc "Create and validate result"
do
  set $result as chart.create "c1" "bar" {"labels": ["Q1","Q2"], "datasets": [{"label": "Sales", "data": [100,200]}]} {"title": "Revenue"}
  if $result != null
    print "Success: " + $result
  else
    print "Operation returned no data"
  end
enddo

Related Modules

• json -- JSON module for complementary functionality